chore(docs): remove the pre-mike Sphinx site from the gh-pages root

- 18 root entries were frozen at 2026-07-07 and never updated again
- an unversioned path returned 200 with superseded content, so a status
  check could not detect the stale link
- the root 404.html went too: its assets point at /Tools/, never /osw-python/
- keeps .nojekyll and every path mike writes

Closes #205

Author: LukasGold